The world’s largest neutrino detector, known as the Jiangmen Underground Neutrino Observatory (JUNO), has officially commenced data collection in Guangdong, China. Located 700 meters underground, JUNO aims to enhance our understanding of neutrinos, often referred to as “ghost particles” due to their elusive nature.
Neutrinos are neutral particles with minimal mass that rarely interact with matter. Despite their abundance in the universe, studying them presents significant challenges. The significance of JUNO lies in its size and technology. The facility houses 20,000 tonnes of liquid scintillator, a substance that emits light when excited by subatomic particles, and is equipped with 43,200 photomultiplier tubes (PMTs) designed to detect this light.
Innovative Design and Purpose
JUNO’s liquid scintillator, primarily composed of linear alkyl benzene, is contained within a large acrylic sphere. This sphere is surrounded by an additional 60,000 tonnes of ultra-pure water, which serves as radiation shielding. This innovative arrangement is similar to that of the Sudbury Neutrino Observatory in Canada but on a much larger scale, allowing for greater sensitivity in detecting neutrinos.
This facility is not only crucial for astroparticle physics; it will also contribute to studies on neutrino oscillations—an intriguing phenomenon where neutrinos switch between three different types, or “flavours.” JUNO will facilitate beam experiments that analyze neutrinos emitted by nearby nuclear reactors, which is significant since most nuclear reactions, including fusion and fission, involve neutrino emissions.
Future Prospects and Competition
While JUNO currently holds the title of the largest neutrino detector, it is set to face competition in 2028 when Japan’s HyperKamiokande begins operations. HyperKamiokande will feature a massive 258,000-tonne water vessel, potentially reclaiming the title. The race to uncover the mysteries of neutrinos underscores the collaborative spirit of scientific inquiry, as results from both facilities will be openly shared, benefiting researchers globally.
As data collection progresses, JUNO is poised to make significant contributions to our understanding of the universe’s fundamental particles, paving the way for breakthroughs in particle physics. The international scientific community eagerly anticipates the insights that will emerge from this groundbreaking facility in China.
